Flexible type mounts in high speed printing machines



Nov. 21, 1967 A. A. SARITI 3,353,432

FLEXIBLE TYPE MOUNTS IN HIGH SPEED PRINTING MACHINES Filed April 11, 1966 I 1 Jim/ I i MM:

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Iifl y fl/mma/A jze/r MKM/ United States Patent 6 3,353,482 FLEXIBLE TYPE MOUNTS IN HIGH SPEED PRINTING MACHINES Anthony A. Sariti, Lake Park, Fla, assignor to Radio Corporation of America, a corporation of Delaware Filed Apr. 11, 1966, Ser. No. 541,632 Claims. (Cl. 101-93) ABSTRACT OF THE DISCLOSURE Printed character smear is alleviated by flexible type character mounts which extend from the surface of a carrier body, for example, a revolvable drum. The type character mounts are relatively thin and flexible in the radial direction and relatively elongated and rigid along a direction parallel to the drum axis, whereby a selected mount flexes during the dwell of a print hammer so that the motion thereof is momentarily retarded.

This invention relates to printer apparatus and particularly to improved high speed printer apparatus of the impact type.

Generally, impact printers include a font of type characters arranged on an endless carrier surface, such as a drum, disc, chain and the like, which is continuously moving to cyclically present each type character to a print station where a print hammer means selectively impacts a printing medium against the moving type characters thereby printing selected character images. This kind of impact printer is often required to operate at high speeds, especially when used with computer equipment wherein printing speeds on the order of 1,000 lines or more per minute are common. When the printer is operated at such high speed, the printed character images are likely to become smeared, depending upon the speed of the type characters and the dwell time of the print hammer.

An object of this invention is to provide new and improved printer apparatus.

Another object is to reduce character smear in high speed printer apparatus.

Yet another object is to reduce the speed of a selected type character during the dwell time of a print hammer.

Briefly, the present invention is embodied in printer apparatus wherein a plurality of character slugs are mounted on the surface of a carrier body. Each of the character slugs is mounted on the carrier surface by a member which is resilient in a first direction along the carrier surface and rigid in a second direction along the surface which is perpendicular to the first direction. The carrier surface and the character slugs mounted thereon are cyclically moving in the resilient direction past a print station, where a print hammer selectively impacts a printing medium against the moving character slugs. At the instant of impact, the mounting member associated with a selected character slug flexes in the direction of motion so that the speed of the selected character slug is retarded during the dwell time of the print hammer, thereby tending to reduce smearing of the printed character image.

In the accompanying drawing, like reference characters denote like elements, and:

FIG. 1 is a schematic diagram of an exemplary printer apparatus in which the present invention can be utilized.

FIG. 2 is a partial blown-up view of a resiliently mounted character slug of the present invention during impact;

FIGS. 3A and 3B are front and left end views, respec- 3,353,482 Patented Nov. 21, 1967 tively, of a portion of the carrier body and surface adapted for the mounting of a character slug;

FIGS. 4A and 4B are front and right end views, respectively, of a character slug adapted for mounting on the carrier surface;

FIGS. 5A and 5B are front and top views, respectively, of a beam mounting member adapted to be used with the carrier surface and character slug structures illustrated in FIGS. 3 and 4; and

FIG. 6 is a front view of the character slug of FIG. 4 mounted on the carrier surface of FIG. 3 by means of the mounting member of FIG. 5.

The present invention is contemplated for use in any impact printer apparatus which includes a font of type character slugs arranged on an endless carrier surface such as a drum, disc, chain and the like, which is con tinuously moving in a manner to cyclically present each type character to a print station where a print hammer means selectively impacts a printing medium against the moving type characters. For sake of convenience, the exemplary printer apparatus in FIG. 1 is illustrated as having a carrier surface 1 which is the peripheral surface of a drum or disc 2. Mounted on the surface 1 are a plurality of type character slugs 3. The type character slugs 3 may be arranged, for example, in columnar fashion on the endless carrier surface 1. The disc 2 is mounted upon a shaft 4 driven by a drive means 5 such that the disc is continuously rotating about the shaft 4 in the clockwise direction, as indicated by the arrow 6, to cyclically present each of the type character slugs 3 to a print station '7. The drive means 5 may be any suitable shaft driving means such as an electric motor.

Included at the print station 7 is a print hammer 9 selectively movable by a solenoid 8 to impact a printing medium against the moving type character slugs 3. The

printing medium includes a record strip 10 such as paper and a marking transfer medium 11 such as a print ribbon. The verticle position of the record strip 10 and the marking transfer medium 11 may be advanced by any suit able feeding arrangement (not shown).

A translator (not shown), which may be a shaft encoder (not shown), determines which of the type character slugs 3 is about to be presented to the printing station 7 and encodes it. The encoded character is transmitted to an input 12 of a comparator and solenoid drive arrangement 14, as illustrated by the dashed line 13. The comparator and solenoid drive arrangement 14 compares the encoded character with input data characters received by way of another input 15 from a data source such as a computer. When an input character corresponds to the encoded character, the comparator and solenoid drive arrangement actuates the solenoid 8 to thereby drive the print hammer 9 to impact the printing medium against the selected moving character slug.

It should be understood that for sake of convenience only one print hammer and one column of character slugs have been illustrated. The printer apparatus may include a plurality of columns (not shown) of character slugs arranged on the carrier surface and a like plurality of printer hammers (not shown) disposed at the print station 7 in one-to-one relation to the character slugs columns. It should be further noted that the carrier 2 may include a plurality of discs mounted on the shaft 4 with each disc having a column of character slugs mounted on its circumferential periphery.

When the print hammer 9 impacts the printing medium against a selected character slug, the hammer dwells or is in contact with the printing medium and character slug for a period of time. Since the selected character slug is moving, there is a tendency for the printed character image to smear. At relatively slow speeds, the character smear is slight and therefore tolerable. However, when the carrier 2 is operated at relatively fast speeds, for example 1,000 or more revolutions per minute, the character smear tends to become so pronounced as to be intolerable.

The present invention tends to reduce character smear at high speeds by retarding the motion of the selected character slug during the dwell time of the print hammer. The character slug motion is retarded by mounting the type character slugs on the carrier surface by means of members which, while under the influence of the impacting print hammer, flex in the direction of motion and remain rigid in the direction perpendicular thereto along the carrier surface. Thus, in FIG. 2, the type character slugs 3 are mounted on the carrier surface 1 by individual members 16 which are normal to the surface 1 and which are resilient in the plane of the motion of the carrier 2 but are rigid with respect to forces perpendicular to the plane of motion.

More specifically, FIG. 2 illustrates a selected type character slug 3,, during impact of the print hammer 9. As the hammer 9 impacts the printing medium against the character slug 3,, the mounting member 16 flexes from its normal position in the plane of motion. The carrier surface 1 continues to move during the dwell time of the print hammer 9. However, due to the fiexure of the member 16,, the selected character slug 3, remains in substantial registration with the printing medium and print hammer. As the print hammer 9 rebounds, the mounting member 16, associated with the selected character slug 3 springs back to its original position.

The invention embodied in FIGS. 1 and 2 can be realized with any suitable mounting means which has the property of resiliency in the plane of motion of the carrier surface and type character slugs. By way of example, FIGS. 3, 4, 5 and 6 illustrate a specific structure which the carrier body, type character slug and mounting member may take. Referring first to FIGS. 5A and 5B, the mounting member 16 is illustrated as a cantilever beam in the form of an I-shaped key, which can be any suitable resilient material such as spring steel. The mounting member 16 is shown to be relatively thin in the front view of FIG. 5A and to be relatively elongated in the top view of FIG. 5B.

FIGS. 3A and 3B show a portion of the carrier body 2 having its surface 1 adapted to receive one end of the I- shaped key mounting member 16 of FIG. 5. Thus, in the front and left end views of FIGS. 3A and 3B, the carrier surface 1 has a channeled receptacle 17 which is adapted to receive the one end of the member 16, illustrated in FIG. 5A. The front and right end views of FIGS. 4A and 4B show a similar channeled receptacle 18 on the bottom surface of the type character slug 3 which is adapted to receive the other end of the I-shaped key mounting member 16. Finally, FIG. 6 shows the composite structure of the type character slug 3 mounted on the surface 1 of the carrier body 2 by the I-shaped key mounting member 16.

Thus, there has been described an improved high speed printer apparatus of the impact type in which character image smear is reduced by retarding the motion of the type character slugs during the dwell time of the print hammer. As mentioned previously, it is apparent that the present invention can be practiced with any endless carrier surface which is revolvable about a central point or axis to present a font of type characters in a cyclical manner to a print station. For example, the drum or disc carrier 2, illustrated in FIG. 1 could be replaced with a chain type carrier.

What is claimed is:

1. Printer apparatus comprising a carrier body having an endless surface, said carrier body being revolvable to impart peripheral motion to said surface,

a plurality of type character mounts extending from said surface, each of said mounts being thin and flexible along a first direction and elongated and rigid along a second direction perpendicular to said first direction,

print hammer means disposed at a print station adjacent said revolvable carrier surface,

a printing medium disposed between said hammer means and said carrier surface, and

means for selectively operating said print hammer means to forcibly place said printing medium against said type character mounts, said first and second directions being aligned along the carrier surface such that a selected type character mount flexes during the dwell of said hammer and print medium against said selected character so that the peripheral motion thereof is momentarily retarded, while there is substantially no flexure or disorientation of the mount along the second direction.

2. The invention according to claim 1 wherein said surface is cylindrical about an axis.

3. The invention according to claim 2 wherein the first direction is radial and the second direction is parallel to the cylindrical axis.

4. The invention according to claim 3 wherein said type character mounts are arranged in a column about said cylindrical surface.

5. The invention according to claim 4 wherein each of said mounts is a cantilever beam in the form of an I-shaped key, and

wherein said I-shaped key mounts are mounted in channeled receptacles on said carrier surface.

References Cited UNITED STATES PATENTS 2,143,833 1/1939 Moss 101-379 2,267,661 12/1941 Meyers 101-111 2,310,644 2/1943 Meyers 101-110 2,919,641 1/1960 Peleger. 2,940,386 6/1960 Cetran et al. 3,041,965 7/1962 Sasaki 101-111 3,071,071 1/1963 Beaver 101-380 3,142,249 1/1963 Sasaki 101-111 3,164,084 1/1965 Paige. 3,169,474 2/1965 Howard 101-110 3,230,880 1/1966 Beaver 101-380 WILLIAM B. PENN, Primary Examiner. 

1. PRINTER APPARATUS COMPRISING A CARRIER BODY HAVING AN ENDLESS SURFACE, SAID CARRIER BODY BEING REVOLVABLE TO IMPART PERIPHERAL MOTION TO SAID SURFACE, A PLURALITY OF TYPE CHARACTER MOUNTS EXTENDING FROM SAID SURFACE, EACH OF SAID MOUNTS BEING THIN AND FLEXIBLE ALONG A FIRST DIRECTION PERPENDICULAR TO SAID FIRST ALONG A SECOND DIRECTION PERPENDICULAR TO SAID FIRST DIRECTION, PRINTING HAMMER MEANS DISPOSED AT A PRINT STATION ADJACENT SAID REVOLVABLE CARRIER SURFACE, A PRINTING MEDIUM DISPOSED BETWEEN SAID HAMMER MEANS AND SAID CARRIER SURFACE, AND MEANS FOR SELECTIVELY OPERATING SAID PRINT HAMMER MEANS TO FORCIBLY PLACE AND PRINTING MEDIUM AGAINST SAID TYPE CHARACTER MOUNTS, SAID FIRST AND SECOND DIRECTIONS BEING ALIGNED ALONG THE CARRIER SURFACE SUCH THAT A SELECTED TYPE CHARACTER MOUNT FLEXES DURING 